Bed nets were hailed as the solution to the malaria epidemic killing thousands of children in tropical parts of the world. But now, years after they were distributed en masse, the mosquitos have developed resistance and the bed nets have holes. In other words, they're not working so well any more.

Governments and charitable organizations have distributed millions of insecticide-treated bed nets across Africa, to repel and kill mosquitoes that spread malaria. But mosquitoes are growing resistant to the insecticide. Health experts say a resurgence of the deadly disease may be coming -- one that could have been avoided.

Governments and charitable organizations have distributed millions of insecticide-treated bed nets across Africa, to repel and kill mosquitoes that spread malaria. But mosquitoes are growing resistant to the insecticide. Health experts say a resurgence of the deadly disease may be coming -- one that could have been avoided.

Bed nets were hailed as the solution to the malaria epidemic killing thousands of children in tropical parts of the world. But now, years after they were distributed en masse, the mosquitos have developed resistance and the bed nets have holes. In other words, they're not working so well any more.